1. Field of the Invention
The present invention relates to a network apparatus connected to a network, a method of controlling the apparatus, and a storage medium.
2. Description of the Related Art
In general, there has been known a method in which a network apparatus (hereinafter also referred to as “a network device”, e.g. an image forming apparatus, such as an MFP) directly connected to a network is managed using a device management protocol, such as SNMP (simple network management protocol). Further, there has been known a system in which an information processing apparatus, such as a personal computer, is connected to a network to perform centralized control of devices connected to the information processing apparatus and the above-mentioned network device such that the devices connected thereto can be distinguished from the network device (see e.g. Japanese Patent Laid-Open Publication No. 2008-27128).
In the device management method described in Japanese Patent Laid-Open Publication No. 2008-27128, the information processing apparatus needs to determine in advance whether or not a device is directly connected to a network (i.e. whether or not the device is a network device), and acquire device information on the network device using SNMP when the device is a network device.
On the other hand, as for a device connected e.g. via USB to the information processing apparatus connected to the network, the information processing apparatus manages the device by sending a request command for acquisition of device information, using a protocol suitable for the connected device. In other words, in the case of making a request for acquisition of device information, the information processing apparatus recognizes the type of an associated device in advance and changes a request command according to the type.
Further, there has been known another device management method in which an information processing apparatus acquires e.g. a system name or the like uniquely assigned to a network device, using a management protocol. In this method, the information processing apparatus changes a request command to a command for making a query to the network device using identification information, such as the acquired system name or the like, to thereby acquire device information from the network device.
However, it is difficult for the information processing apparatus to determine in advance whether a device is connected to a network directly or via another information processing apparatus. When it is impossible to determine in advance how the device is connected to the network, the information processing apparatus cannot change the request command, resulting in a trouble in gathering necessary device information.
MIB (management information base) information that can be acquired using SNMP includes e.g. two types of MIB variables, i.e. scalar and table. The scalar MIB variable has a single value. For example, a scalar MIB object sysDescr (see 203 in FIG. 2) is read-only information. The value of this MIB object is a character string describing a network device, and is a type of information which has only one value associated with the network device.
On the other hand, the table MIB variable can show a plurality of similar information items as table information. For example, it is possible to show information on toner as a consumable using values of a MIB object “prtMarkerSuppliesDescription” (see 310 in FIG. 3) such that information items on four color toners, i.e. cyan (C) toner, magenta (M) toner, yellow (Y) toner, and black (K) toner, can be separately listed.
In a general information processing apparatus, device identification is performed using scalar information which has only one value associated with a network device and is read-only, and then optimization is performed e.g. by switching logic for acquisition of detailed management information.
For this reason, between information processing apparatuses using respective different software programs, a case occurs where one information processing apparatus can identify a device, but another cannot. In this case, detailed information on a network device and the status of the network device can be managed only in information processing apparatuses using software programs capable of identifying the device, but information processing apparatuses using the other software programs cannot manage the device, which degrades user friendliness.